Events

Events at Physics

<< Summer 2015 Fall 2015 Spring 2016 >>
Subscribe your calendar or receive email announcements of events

Events During the Week of September 27th through October 4th, 2015

Monday, September 28th, 2015

Plasma Physics (Physics/ECE/NE 922) Seminar
Linear and non-linear 3D plasma response for tokamak control
Time: 12:00 pm - 1:00 pm
Place: 2241 Physics Bldg
Speaker: Carlos Paz Soldan, General Atomics
Abstract: A recent upgrade of the DIII-D tokamak magnetic diagnostic is providing new insights to our understanding of the plasma response to external non-axisymmetric (3D) perturbations This talk will highlight two challenges for 3D control in tokamaks: 1) correction of long wavelength fields for error field (EF) control, and 2) application of short wavelength fields for edge-localized mode (ELM) control. Correlation of optimal control with 3D response measurements identifies the underlying tokamak linear instabilities mediating EF and ELM control - and reveals their dissimilarity. While linear physics governs which responses are important, at their extreme both EF and ELM control fields trigger similar non-linear bifurcations. This highlights the potential of driven reconnection (3D field penetration) to provide a common physical framework for both effects.
Add this event to your calendar

Tuesday, September 29th, 2015

Chaos & Complex Systems Seminar
What’s a “bone attack” and why should I care?
Time: 12:05 pm - 1:00 pm
Place: 4274 Chamberlin (refreshments will be served)
Speaker: Neil Binkley, UW Institute on Aging
Abstract: We all know that heart attacks signify artery disease and that they may cause disability and even death. However, many people do not appreciate that fractures (broken bones) in older adults, what we are calling “bone attacks,” similarly indicate underlying bone and muscle disease. A Bone Attack is a broken bone (fracture) occurring in an adult age 50+ from a fall or other minimally traumatic event. Bone attacks are common and occur in 1:2 women and 1:4 men over 50. Fractures of the spine, hip and forearm are the most common types, but rib, pelvis and upper arm fractures also occur. Bone attacks, like heart attacks, are serious health events that may cause disability and even death. Indeed, 20-30% of older adults who break their hip die within one year and approximately half of those who survive a hip fracture require assistance with everyday activities and approximately 1/3 require nursing home care, some permanently.<br>
<br>
Bone attacks (fractures) result from osteoporosis (bone loss) and sarcopenia (muscle loss) in older adults. In essence, both our bone and muscle strength decline as we age. This combination increases our risk for falling and when falls occur onto weakened bones, bone attacks (fractures) result. The likelihood of these fractures is increased by obesity and diabetes. Despite the high prevalence of these bone attacks, they remain largely ignored by physicians, patients and the healthcare system. It’s time for a change.
Host: Sprott
Add this event to your calendar
Theory Seminar (High Energy/Cosmology)
Cosmological Constraints on the Gravitational Interactions of Matter and Dark Matter
Time: 3:00 pm - 4:00 pm
Place: 5280 Chamberlin Hall
Speaker: Ben Stefanek, University of Wisconsin-Madison
Abstract: Although there is overwhelming evidence of dark matter from its gravitational interaction, we still do not know its precise gravitational interaction strength or whether it obeys the equivalence principle. Using the latest available cosmological data and working within the framework of LambdaCDM, we first update the measurement of the Newton's constant for all matter: $G_N=7.26^{+0.27}_{-0.27}times 10^{-11} m^3 kg^{-1} s^{-2}$, which differs by $2.2 sigma$ from the standard laboratory-based value. In general relativity, dark matter equivalence principle breaking can be mimicked by a long-range dark matter force mediated by an ultra light scalar field. Using the Planck three year data, we find that the dark matter "fifth-force" strength is constrained to be weaker than $10^{-4}$ of the gravitational force. We also introduce a phenomenological, post-Newtonian two-fluid description to explicitly break the equivalence principle by introducing a difference between dark matter inertial and gravitational masses. Depending on the decoupling time of the dark matter and ordinary matter fluids, the ratio of the dark matter gravitational mass to inertial mass is constrained to be unity at the $10^{-6}$ level.
Host: Amol Upadhye
Add this event to your calendar
Prospective Undergraduate Majors in Physics -- PUMP Meeting
Time: 3:30 pm
Place: 2103 Chamberlin Hall
Speaker: Physics Department
Abstract: Are you interested in physics?

Want to know more:

Why Major in Physics
What Can You do with a Physics Degree
Major Requirements
Undergraduate Research Opportunities
Tutoring & Mentoring Opportunities
Poster: https://www.physics.wisc.edu/events/posters/2015/3817.pdf
Add this event to your calendar

Wednesday, September 30th, 2015

Department Meeting
Time: 12:15 pm
Place: 5310 Chamberlin Hall
Add this event to your calendar

Thursday, October 1st, 2015

R. G. Herb Condensed Matter Seminar
Tunable mid-infrared photonics
Time: 10:00 am
Place: 5310 Chamberlin Hall
Speaker: Mikhail Kats
Abstract: The mid-infrared (mid-IR) spectral range (wavelengths from ~ 2 μm to ~20 μm) has recently become more important for both applications and fundamental science. However, compared to their counterparts in the visible, optical components in the mid-IR are still significantly under-developed.
We create tunable optical components for the mid-IR by incorporating materials that respond to temperature, current, or applied electric field into photonic structures such as interference coatings and optical metasurfaces. In particular, we exploited the insulator-to-metal phase transition of vanadium dioxide (VO2) to create temperature- and current-tunable modulators and thermal emitters, and used electrostatic doping in graphene to construct reconfigurable metasurfaces that operate at nanosecond time scales.
Host: Saffman
Add this event to your calendar
Cosmology Journal Club
An Informal discussion about a broad variety of arXiv papers related to Cosmology
Time: 12:15 pm
Place: 5242 Chamberlin Hall
Abstract: Please visit the following link for more details:
    http://cmb.physics.wisc.edu/journal/index.html
Please feel free to bring your lunch!
If you have questions or comments about this journal club, would like to propose a topic or volunteer to introduce a paper, please email Le Zhang (lzhang263@wisc.edu)
Host: Peter Timbie
Add this event to your calendar
NPAC (Nuclear/Particle/Astro/Cosmo) Forum
Spectral and flavor composition of the ultrahigh energy neutrinos seen at IceCube
Time: 2:30 pm - 3:30 pm
Place: 4274 Chamberlin Hall
Speaker: Aaron Vincent, Institute for Particle Physics Phenomenology , Durham University
Abstract: I will present the main elements of our independent studies of the high-energy events seen above 28TeV by IceCube, arXiv:1404.0017 and arXiv:1502.02649. I will cover the physics involved, and show the effect of modelling and assumptions on the conclusions one can reach about the flavor composition, spectrum, and background rates. I will compare our results and methodology with the official IceCube studies, and discuss future prospects.
Host: Carlos Arguelles Delgado
Add this event to your calendar
Graduate Introductory Seminar
Quantum Computing
Time: 4:30 pm - 5:30 pm
Place: 5280 Chamberlin Hall
Speaker: Coppersmith, Eriksson, Joynt, McDermott, Saffman, Vavilov, Walker, Yavuz
Add this event to your calendar

Friday, October 2nd, 2015

Atomic Physics Seminar
Advanced quantum communication using hyperentangled photons
Time: 10:00 am
Place: 5310 Chamberlin Hall
Speaker: Trent Graham , Urbana-Champaign
Abstract: Photons are the perfect "flying qubits" for quantum communication: they travel at the speed of light and have only weak nonlinear interactions with their environment. While these features make photons ideal carriers of quantum information, many quantum communication protocols require qubits to interact in quantum logic gates. Although interactions between individual photons are too weak for reliable multi-qubit gates, it is relatively easy to implement efficient gates between different degrees of freedom encoded on the same photon. By using photons that are simultaneously entangled in multiple degrees of freedom ("hyperentangled") we can perform operations that are impossible for single-qubit states, as well as gain access to higher dimensional entanglement. We demonstrate that hyperentangled states can be used for efficient quantum state communication, increased classical channel capacity, and more efficient quantum channel characterization.
Host: Saffman
Add this event to your calendar
Physics Department Colloquium
Taming Turbulence in Magnetized Plasmas: From Plasmas for Fusion Energy to Black Hole Accretion Disks
Time: 3:30 pm - 4:30 pm
Place: Chamberlin 2241 (coffee & Cookies at 3:15pm)
Speaker: Troy Carter, UCLA
Abstract: Plasmas in the laboratory and in astrophysical settings vary widely in parameters (e.g. temperature and density) but have one thing in common: they are plagued by instability. Instabilities and associated turbulence are detrimental in laboratory plasmas for fusion energy research, causing heat, particles and momentum to "leak" across the confining magnetic field. In astrophysical plasmas like accretion disks, turbulence is often essential to explain observed rates of momentum transport and accretion. I will talk about instabilities and turbulence in magnetized plasmas and their relevance to achieving magnetic confinement fusion in the laboratory and understanding processes in astrophysical plasmas.
Host: Forest
Poster: https://www.physics.wisc.edu/events/posters/2015/3696.pdf
Add this event to your calendar